my customer has ASC ver. 3.3.3 as primary at windows server and secondary is new and ACS 4.0 is installed on it but is free from data.
Qes : they asking if we can replicate the database between primary acs 3.3.3 and secondary 4.0 then after that we remove primary from the network where the secondary will be primary ,we will upgrade 3.3.3 to 4.0 then will reconnect it to the network after testing.
that is only they want to avoid down time
plz give the best advise and solution